Clean up Args+Mode coupling
use better constructor in test to see exceptions
Put in the mode on clone
Fix + on ArgsMode
Add IRC notification support to .travis.yml
Adds Scalding specific repl.
Merge pull request #610 from jhlch/repl-refactor

Repl refactoring
Thank Juliet and link to the full list of contributors.
Merge pull request #687 from twitter/modeFix

Clean up Args+Mode coupling
Add DateRange.length
Merge pull request #688 from twitter/daterange-length

Add DateRange.length